There has long been a desire to transplants plants from a first container to a second container so that plant growth may continue, plant health may be enhanced, the plant may be re-established in a container that is more appropriate for sale to consumers and that enables or enhances plant growth to an optimally marketable size and condition, or for other reasons. More specifically, often the plant that is to be transplanted is a propagule that has spent at least some time growing in a container (or cell) of what may be referred to as a propagule tray, the term tray including a multi-celled arrangement for containing plants. Such a propagule tray typically contains several cells in most or all of which one or more propagules is established. For certain reasons (e.g., because production efficiency is enhanced and production costs are lowered), the propagule is, at some point in its early life (e.g., as a seed) established and in and allowed to grow in a container (again, a cell) that is smaller (volumetrically and areally, e.g.) than the container in which it is ultimately presented during sale to the consumer (the larger container may be referred to as a cell of an adolescent tray). Thus, there must be a transplant event in order to re-plant or re-establish the plant (e.g., the propagule) from the cell of the propagule tray to the cell of the adolescent tray.
For quite a while now, many greenhouses have been relying on a plant punch achieved through the use of a plant punch machine to cause a plant transplant, whether it be for the reason indicated above or other reasons. Typically, a tray with larger cells (e.g., an adolescent tray) that contain soil is placed below a tray with smaller cells, at least some of which contain soil and one or more plants (e.g., propagules). Upon correctly positioning the two trays relative to each other, a plant punch may be caused to transplant one or more plants of the smaller cells of the upper tray into the larger cells of the lower tray. An actual, individual punch may be caused by a plant punch element (having a plant punch head) that has a lower surface that acts to apply a downward force from above the plant to be punched so that it is forceably removed from its smaller cell and re-located downwardly and into the soil of a larger cell of the lower tray. The plant punch element may then be brought back up to an upper position, establishing a plant punch cycle. Typically, more than one plant is punched at a time—e.g., more than one of the containers of the lower tray may be filled during one cycle of the plant punch apparatus (which, of course, would typically move more than one plant punch element). It should also be understood that more than one lower tray may be transplanted into during a plant punch cycle, although typically only one tray is established below the upper tray at one time. For purposes of clarity, this discussion will focus on the case where only one tray at a time is established below the upper tray.
After the plant is transplanted in the below-established tray, any of several events may take place. If the plant punch cycle effected a transplant of all the plants that it was desired to transplant into that tray, (e.g., perhaps all the cells of the below-established tray had a plant transplanted into them), then the lower tray may be removed from below the upper tray and replaced with a tray into which it is desired to transplant at least one plant from the upper tray. However, it may be that the plant punch (a term that may refer individually to one plant punch or collectively to a plurality of punches that transplant more than one plant during one cycle) does not transplant a plant into each cell of the lower tray—if it is desired to fill all the cells of the lower tray, then the lower tray is not replaced after one cycle, but instead the lower tray and the plant punch element(s) may be adequately horizontally moved relative to each other so at least some of the “unfilled” (a term used to refer merely to the absence of a plant) cell(s) of the lower tray can be filled (e.g., have a plant transplanted into them) during an additional plant punch cycle. After as many plants are transplanted into the lower tray as desired, the lower tray may be replaced so that a different tray may be
Of course, if more than one plant is to be punched during one cycle, then it is necessary that the plant punch apparatus have more than one plant punch element (as, typically, only one plant is punched per plant punch element during one plant punch cycle). As is well known in the art, regardless of whether all of the plants that it is desired to transplant into the lower tray are transplanted in one plant punch cycle, it is necessary to horizontally move the plant punch element(s) relative to the upper tray after one plant punch cycle in order to punch additional plants from the upper tray during an additional cycle. Although this is typically occurs by adequately horizontally moving the upper tray (e.g., in an indexing fashion) without moving the plant punch element(s), it may be also be achieved by adequately horizontally moving the plant punch element(s).
Although the basic plant punch method has evolved over several years, there are still problems that plague its implementation to transplant plants. Among these problems is physical damage of the plant inflicted during the plant punch.(or a lower surface of it) because the known method described immediately above also involves the step of forceably lowering the plant punch element directly onto the plant in order to effect the transplant of that plant. When the plant punch element descends directly on the plant, surfaces of the plant punch (including but not limited to its lower surface) directly contact parts of the plant, first contacting the upper portion of the plant and then the soil emerging plant structure (e.g., one or more stems) that emerge from the soil of the plant and support the plant's upper portions. Even though at times the surfaces of the plant punch element (including, importantly, a lower surface) might not directly contact a part of the plant (e.g., where the stem of a plant is separated during the punch event from the lower surface of the plant punch element by the upper portions of the plant that are sandwiched in between), that part of the plant could still be damaged because of the force applied indirectly to it. Further damage to plant parts (especially upper, leafy parts of the plant) may be caused not necessarily from the plant punch element, but instead from the soil in which the plant to be punched was initially established, as amounts of this soil that surround that soil that is punched downward may collapse into the upper portions of the plant during the plant punch and drag against the upper portions of the plant as they are moved downward. These two types of plant damage—whether resulting from the plant punch element as it is pressured against the plant to effect the downward re-positioning of the plant, or resulting from the “drag” of plant parts against soil of the upper tray's cell during the plant punch—individually and collectively can kill the plant, injure the plant, compromise the plant's ability to survive the stressful transplant and/or compromise the plant's growth after the plant punch, as but a few problems. Also, the approach described immediately above can cause a re-alignment of the plant to a misaligned position during the plant punch, with a resultant inadequately established transplanted plant. Each of these potential results attributable to known methods can cause a reduction in operational and production efficiency; higher production costs; and an overall decrease in greenhouse output and ability to meet consumer demand. The inventive technology disclosed and claimed herein seeks to alleviate or eliminate some or all of these problems.